


Taking The Heat

by wordbending



Category: Undertale (Video Game)
Genre: Alphyne-Centric, F/F, Sickfic, going with a heat theme with my fics apparently
Language: English
Status: Completed
Published: 2018-07-22
Updated: 2018-07-22
Packaged: 2019-06-14 18:21:43
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,614
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/15394692
Author URL: https://archiveofourown.org/users/wordbending/pseuds/wordbending
Summary: In which Undyne learns that fishes and underground volcanoes don't mix.





	Taking The Heat

**Author's Note:**

  * For [IvySnowy](https://archiveofourown.org/users/IvySnowy/gifts).



> Requested by Ivy for the [nonsexual acts of intimacy](http://wordbending.tumblr.com/post/174951682722/nonsexual-acts-of-intimacy-select-from-the) meme - caring for each other while ill! Thanks so much!

“A-a-and then Mew Mew transforms into her s-super form -  you… you know, the one where there’s a s-stock animation that’s, like, w-way higher-budget than all the rest of the… the episode?”

“Yeah! And it ROCKS EVERY TIME! I want to be a cool transforming magical girl too!”

“O-o-oh my. Well. That’s fun to imagine.”

“What?”

“N-nothing! I… I didn’t say anything, Undyne!”

“Well, whatever! So then… whew… then what happens?”

“OK, so Mew Mew says her c-catchphrase, ‘For the sake of love and justice, I will defeat you!’ and then she a-activates her p-power…”

“Wait, hold on…”

“H-huh?”

“I’m… getting kind of winded…”

“...W-where are you?”

“In Hotland, where… where else? Never know… never know where a human might show up!”

“Hotland?! Don’t tell me… don’t tell me you’re in your armor!”

“Uh, duh? I can’t go... hunting humans… without it...”

“Undyne?”

“Wait… is that... a…”

“Undyne?!”

“...”

“Undyne!!! I’m coming to get you! Don’t you dare… don’t you dare die on me!”

* * *

When Undyne woke up, she found herself lying not on a hot, rocky floor, but on a pleasantly warm, comfortable bed. She wasn’t in her armor either - she was in, of all things, nothing but her underwear. There were bags of ice under her armpits, for some reason.

And the human that she swore she’d seen just before she’d collapsed was nowhere to be found either.

It took her a moment, and noticing the giant Mew Mew Kissy Cutie poster on the wall, to realize she was in Alphys’ lab. Surrounding the bed was a small army of giant portable fans, with barely any space for anyone to move through them.

“NGGGGGAHHHHHH!!!” she screamed, jumping up on top of the bed, barely even mindful of her lack of clothing. The bags of ice fell onto the bedsheets. “What… what am I doing here?! The human… the human’s gonna get away!!!”

Belatedly, she realized Alphys was right in front of her. And staring at her. Her face was a very, very dark shade of red. She was holding a paper cup, which she promptly dropped, splashing water all over the floor and the bottom of her lab coat.

“O-o-oh,” said Alphys, eventually. “You’re… you’re up.”

“Alphys?!” Undyne continued shouting. “Did you _undress me?!”_

Alphys’ face turned even redder, her glasses fogging up. Her shoulders stiffened as she very awkwardly started to make her way towards the escalator. In a loud, monotone voice, she shouted, “I’M GOING TO GO GET YOU SOME MORE WATER.”

“W-wait! I didn’t mean…” Undyne tried to say, feeling her own cheeks getting warm, but Alphys was already gone.

By the time Alphys returned with a new cup of water, glasses unfogged and face slightly less red, Undyne had sat down on the edge of the bed, her arms crossed.

“Undyne… y-y-you need to l-lay down,” Alphys stammered.

“No! I’m fine! I _need_ to go fight the human!” Undyne insisted. She remembered having seen one just before she’d collapsed - she was sure of it! “This is my big chance!”

“Undyne, there… there _is_ no h-human,” Alphys said patiently. “I… I would h-have seen t-them with my c-c-cameras.”

“Then... what did I see...?”

“P-probably a hal-hallucination.” Alphys took a seat next to Undyne, and Undyne for the first time noticed the chair that was sitting by the bed. How long had Alphys been sitting there, waiting for her to wake up? “Now… now please d-drink this.”

Swallowing her righteous fury just long enough to feel a little bit guilty, Undyne nodded. Alphys, though, didn’t hand her the paper cup.

“Y-y-you’re probably too w-weak to hold this,” Alphys explained. “L-let me.”

Undyne hated to hear she was too weak to do _anything_ , but she uncrossed her arms and nodded again. Alphys walked up to her and raised the cup to her mouth, and Undyne opened it obediently and drank.

Once the cup was empty, Alphys threw it into a nearby wastebasket, which Undyne noticed was full of paper cups. And, for whatever reason, broken thermometers.

Alphys leaned up as much as she was physically able to and pressed the back of her hand against Undyne’s head. It immediately let out a _sizzle,_ and with a hiss, Alphys withdrew her hand and started to shake it.

“Still p-plenty hot,” she said, blowing on her fingers. “T-that’s not good.”

Undyne was confused. “What does that mean?”

Alphys frowned, slowly waving her hands in circles as she spoke. “It means… it means the m-magic in you is d-destabilizing. I-if it keeps up, you c-could… you c-could even… Fall Down.”

Undyne felt vaguely sick. “O-oh.”

“You h-have plenty of D-Determination, but… I’m l-lucky I caught you when I d-did.” Her eyes widened as she seemed to realize she’d said something. “I mean, uh, _y-y-you’re_ l-lucky! Of c-course!”

Undyne didn’t know what Determination was, or why it sounded so important that she felt it needed capital letters, but she knew that Alphys was right. She had been lucky to have had Alphys find her when she collapsed, or who knew what could have happened.

And she’d utterly _hate_ to do anything, anything at all, to hurt Alphys.

Undyne reached out a hand to reassuringly pat Alphys’ shoulder, but she pulled away when she realized she’d probably only burn it.

“So what now, Doc?” she asked.

“N-now… now you should rest,” Alphys said. “I’ll… I’ll keep g-giving you w-water, but you need s-sleep.”

Undyne scoffed. Sleep was for people like Sans! It wasn’t for members of the Royal Guard like her! She barely even used her _bed!_

“Undyne…” Alphys warned.

“OK, OK, fine,” Undyne replied, sighing. With a flop, she laid down on one of Alphys’ pillows. “I’ll do it for _you,_ Alphys. _”_

“T-thanks, Undyne,” said Alphys, before walking off towards her bookshelf. “H-here, I’ll read you o-one of my f-favorite mang… I-I mean, human history b-books! T-that should help!”

When she returned a minute later, holding volume 12 of _Moe-Moe’s Odd Odyssey,_ Undyne was already starting to drift off. She had been ignoring it before, but now that she was alone, she’d noticed just how _hot_ it was in the room, even with all those fans running. It was enough to make Hotland feel like a nice dip in Waterfall.

“S-so, l-last volume, Moetaro h-had just activated h-her Walkman…” she started to say. “And Paula, or, um, Paura, d-depending on your t-translation, had a-activated her Walkman and was going to f-fight her…”

As Alphys continued to talk, Undyne continued to drift off further and further. She was barely keeping her eye open.

“ _Yare yare daze…”_ said Alphys, showing her the page she was on, where a young, big-eyed human in what was probably supposed to be a school uniform was pointing at a young, big-eyed human with prayer beads around her neck. “You’re two-thousand years too early to fight me…”

Undyne fell asleep.

* * *

Suddenly, Undyne found herself being sprayed with water. In the face. She sputtered, sitting up from the bed, which for a minute was completely soaked. But the bed simply absorbed the water like a sponge.

Alphys turned off the garden hose she was holding and gasped.

“I’m… I’m s-s-so sorry!” she wailed, clenching her hands together. “You f-fell asleep and I thought… I thought you w-wouldn’t get up a-again!”

“YOU TOLD ME TO REST!!!”

Alphys scratched the back of her frills. “...Oh y-yeah. I did.”

Undyne shook a fist. “What the heck, Alphys!”

“B-b-but you still n-need to be r-regularly sprayed with water!” Alphys insisted. “I read it o-online and I, I figured, you know, you being a f-fish and all... n-not to mention that I couldn’t take you o-outside! You’d… you’d burn up again! That’s why… that’s why I b-b-built and installed the Conveniently Water Absorbent Mattress Made Entirely Out Of Sponges!”

Undyne sighed. “Alright, alright, fine. You win.”

“Um, a-anyway,” Alphys said, handing her a towel. Undyne gratefully took it and wiped the water off her face. “Once you, um, get dry, I… I have a t-treat.”

Undyne didn’t have ears, but if she did, they would have perked up. “Oh yeah?”

“Y-yeah! That p-pink stuff you like! The o-one that’s _definitely_ not i-ice cream! I, um…” She shyly scuffed a foot against the floor, which Undyne thought might be the most adorable thing ever known to monsterkind. “Actually brought t-two bowls.”

“To share?!” Undyne said immediately.

“W-w-well,” Alphys replied, waving her hands wildly. “J-j-just in case you m-might be, um, hungry? Yeah! Or… um, maybe… to share…”

Undyne grinned, not even caring about Alphys’ flimsy excuses. “Hell yeah! What flavor?”

“Seagrass.”

“Alright! My favorite!”

Alphys smiled, her tail wagging. “G-great! I’ll… I’ll be right back with it!”

When Alphys returned with the seagrass-flavored pink stuff, Undyne dug into it like she hadn’t eaten in days. Which, well, she might not have. She had no idea how long she’d been out for.

“Oh man, this is _delicious,_ Alphys!”

Alphys swallowed the bite she was eating and smiled back at her. “T-thanks! I’m… I’m really glad you like it.”

“Like it?! I love it! How do you make this stuff anyway?!”

“W-w-well, it’s kind of a c-complicated process,” Alphys started to explain, “but first, I g-go into Waterfall and…”

Undyne, though, zoned out during the whole thing and just continued devouring the contents of the bowl. She didn’t understand a word of what Alphys was saying anyway - she just liked hearing her talk.

* * *

When Papyrus burst up the downwards escalator in Alphys’ lab, he was carrying a bouquet of flowers that didn’t even grow in the Underground and a blue balloon saying “GET WELL SOON!”, which Undyne _also_ wasn’t sure where he’d picked up.

“I, THE GREAT PAPYRUS, HAVE, OF COURSE, NEVER ONCE GOTTEN SICK,” he said. “BUT, AS WE ARE FRIENDS, I NONETHELESS WISH YOU ALL THE BEST IN YOUR RECOVERY, UNDYNE!”

“as a friend: me too.”

Undyne looked past Papyrus. Standing behind him was Sans, carrying a single Echo Flower, which repeated his deadpan “me too.”

“We are _not_ friends,” said Undyne.

“WHY, UNDYNE, I’M HURT!” said Papyrus. “I THOUGHT WE WERE ALREADY BESTIES!”

“Not you, Paps!” Undyne shouted. “I meant _him!”_

Sans merely shrugged.

“hey. maybe someday.”

“hey,” said the Echo Flower in his hand. “maybe someday.”

“Aren’t you supposed to be working?” Undyne asked.

“YES,” said Papyrus, squinting at him. “ACTUALLY, SANS, NOW THAT I THINK OF IT… WHEN DID I TELL YOU I WAS COMING?”

Sans winked. “i had a gut feeling.”

“WAS THAT A SKELETON PUN? THAT WAS ESPECIALLY TERRIBLE! YOU DIDN’T EVEN TICKLE MY _FUNNY BONE!_ NYEH HEH. _”_

“Ugh,” Undyne groaned.

Suddenly, Alphys pushed past Papyrus, carrying another paper cup full of water.

“That’s e-e-enough c-commotion, you two!” she said. “U-Undyne needs r-r-rest!”

“And you need to find that human I told you about on the phone!” Undyne said, waving a finger at Papyrus. “Hop to it!”

Papyrus saluted. “ON THE DOUBLE! NO, THE TRIPLE!”

“And _you…”_ Undyne continued, waving her finger at where Sans had been. But he was already gone, the only proof of him having been there the Echo Flower still repeating every word they were saying. “Whatever. Forget it.”

“WELL, I WILL TAKE MY LEAVE THEN,” said Papyrus, setting his bouquet of flowers and his balloon on the floor, next to the Echo Flower. “REST ASSURED, UNDYNE! I _WILL_ CAPTURE THIS HUMAN!”

And he started to hopscotch out of the room and down the upwards escalator.

When he finally left, Alphys turned to Undyne, giving her the cup of water. Undyne’s hands shook a little as she lifted it to her mouth, but she was still able to drink it.

“Why d-did you tell him you s-saw a h-human anyway?” Alphys asked, frowning. “I t-told you... it was p-probably, um, a h-hallucination.”

“It keeps him motivated,” Undyne answered simply, once she’d finished off the cup. “Uh, not that he really needs it. But, honestly, you know what? I just like seeing him happy.”

* * *

Alphys placed the back of her hand against Undyne’s forehead and, this time, it didn’t sizzle. Alphys let out a sigh of relief and took out a thermometer, placing it in Undyne’s mouth.

“You’re… you’re still r-running a f-fever,” Alphys said, once the thermometer beeped and she looked at the results.  “W-well. I th-think so. You _are_ a f-fish. You p-probably just need to stay in a c-cool environment for a w-while.”

“So I’m free to go?!” Undyne shouted, nearly tackling Alphys as she launched forward and wrapped her arms around Alphys’ neck. “Hell yeah!”

Alphys’ cheeks turned bright red.

“U-u-uh, w-well, I, um, didn’t, uh, say that…” she muttered. “But… but if you r-really _want_ to, I, I suppose i-it couldn’t hurt.”

“Aww, Alphy, are you going to miss me?” Undyne teased, grinning. Just as she expected, Alphys’ body stiffened up in her arms.

“N-n-no, of course… of course not!” Alphys said quickly. “I mean, uh, of c-course I will! I mean…” She laid her head against Undyne’s shoulder, clearly defeated. “Oh dear…”

“Awwww, Alphys, I’m sorry,” Undyne cooed, not letting go of the hug for even a moment. She patted Alphys’ shoulder. “I’m gonna miss you too, you know! This is the most awesome sickness I’ve ever had!”

“R-really?” said Alphys.

“Yeah! I had a ton of fun!”

“Well, I’m g-glad, but, um… promise me… promise me you won’t do this again?”

“Fiiiiiiine.” Undyne broke away from the hug, put one arm over her chest, and raised the other one into the air. “I solemnly swear, on my honor as a Royal Guard, that I won’t run around Hotland in my armor again.”

Alphys looked relieved, even though Undyne wasn’t sure how much Alphys really believed her. “T-thank you.”

“Speaking of which… where is my armor anyway?”

Alphys smiled sheepishly. “O-oh. T-that. I, uh, might have... l-left it in Hotland.”

“WHAT?!”

Alphys raised both hands. “I couldn’t… I couldn’t carry you in it!”

Undyne buried her face in her hands. “Oh no. It’s probably goop by now…”

* * *

When they went back to Hotland, Undyne wearing one of Alphys’ spare Mew Mew Kissy Cutie brand pajamas, they discovered that Undyne’s old armor was, indeed, a pile of magical goop.

“It… it must have d-destabilized in the h-heat,” Alphys sighed, poking at the mess with a claw. “I’ll m-make you a new one.”

Undyne sighed. “I really liked that armor…”

“I k-know! I’m… I’m really sorry.”

“Aww, Alphys, it’s OK. I know you didn’t mean it!” Undyne grinned. “And, besides, I’m sure your next armor will be kickass!”

“Oh, while… while w-we’re here,” said Alphys, suddenly standing up. “I want to… to show off my new i-invention!”

“Oh yeah?” Undyne said, her eye widening. “What is it?”

“You’ll… you’ll see!” Alphys said, walking away from the lab and towards the bridge leading to Sans’ sentry station. Undyne followed behind her, curious.

The two of them shortly arrived at a moderately large white device. It had a giant container filled with water at the top of it, two red and blue faucets at the bottom, and a row of little paper cups attached to a dispenser on its right side.

Undyne stared at it. “What is it.”

“I call it…” Alphys announced proudly, waving her hands towards it. “A Water Cooler! It… um, it keeps water cold, o-obviously, but it even keeps it cold in the scorching t-temperatures of Hotland. With this, you can s-safely stay in Hotland for l-longer periods of time!”

Undyne gasped. “Really?!”

“Yeah!”

“You made this… for… for me?” Undyne said, nearly crying.

“That’s right!”

Once again, Undyne nearly knocked Alphys over hugging her. “Thanks so much! You’re the best, Alphys!”

In Undyne’s arms, Alphys beamed.

“I should get sick more often!” Undyne added.

“P-p-please don’t.”

**Author's Note:**

> Thank you to my friend Skirmisher for taking a look at this fic for me!


End file.
